Thioredoxin-Linked Changes in Enzymes and Storage Proteins

酶和储存蛋白中与硫氧还蛋白相关的变化

• 批准号: 9316496
• 负责人: Bob Buchanan
• 金额: $ 22.5万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-02-01 至 1997-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9316496&HistoricalAwards=false
• 关键词: Thioredoxin; Linked; Changes; Enzymes; Storage

Buchanan 9316496 This proposal is based on recent evidence that the NADP/thioredoxin system (consisting of thioredoxin h, NADP-thioredoxin reductase and NADPH) functions in seed germination. Thioredoxin specifically reduces major storage proteins of cereals (gliadins and glutenins in wheat), thereby enhancing their solubility and susceptibility to proteinases, and reductively inactivates a disulfide protein that inhibits alpha-amylase, an enzyme of starch degradation (barley alpha-amylase/subtilisin inhibitor). An extension of this research has shown that the thioredoxin system strengthens the gluten protein network, thereby enhancing bread quality, and inactivates trypsin inhibitor proteins, thereby potentially improving the nutritional quality of soybean. A patent application covering these findings has been filed, and precommercial development of thioredoxin technology has commenced. The proposed research addresses fundamental new questions: (1) Does thioredoxin have additional regulatory functions in the germination of cereals such as wheat? (2) What changes in redox state and abundance does thioredoxin undergo during germination? (3) Does the activity of enzymes necessary for the reduction of thioredoxin change during germination? (4) Does thioredoxin function in the germination of other types of seeds such as soybean?. The research will add to our understanding of thioredoxin function, enzyme regulation and seed germination. %%% This proposal stems from research in which we have presented evidence for an enzyme system (the "thioredoxin system") that functions as the earliest known signal triggering the germination of cereals such as wheat. The thioredoxin system functions by (1) activating storage proteins of the grain, thereby enabling their use as a source of nitrogen and energy by the seedling, and (2) activating enzymes required for the degradation of starch, thereby enhancing energy production in the early phase of germination. An extension of this research indicates that the thioredoxin system is of technological value. Application of the system to flour strengthens gluten and enhances bread quality. The thioredoxin system also neutralizes plant protein inhibitors of animal digestive enzymes. Application of the thioredoxin system to foods like soybean may enhance their nutritional quality. A patent application covering these uses has been filed, and precommercial development of thioredoxin technology has commenced. The current project represents an extension of the fundamental aspects of this research. The experiments planned will show whether the thioredoxin system has additional functions in wheat and whether the system is important in the germination of other seed types. ***

布坎南9316496这一建议是基于最近的证据，即硫氧还蛋白/硫氧还蛋白系统(由硫氧还蛋白h、硫氧还蛋白还原酶和NADPH组成)在种子萌发中起作用。硫氧还蛋白特异性地降低谷物的主要储存蛋白(小麦中的醇溶蛋白和谷蛋白)，从而提高它们的溶解性和对蛋白酶的敏感性，并还原地灭活一种抑制淀粉降解的酶-α-淀粉酶的二硫键蛋白(大麦-α-淀粉酶/枯草杆菌蛋白抑制剂)。这项研究的延伸表明，硫氧还蛋白系统加强了面筋蛋白网络，从而提高了面包的质量，并使胰蛋白酶抑制蛋白失活，从而潜在地改善了大豆的营养品质。涵盖这些发现的专利申请已经提交，硫氧还蛋白技术的商业化前开发已经开始。这项拟议的研究解决了基本的新问题：(1)硫氧还蛋白在小麦等谷物的萌发中是否具有额外的调节功能？(2)硫氧还蛋白在萌发过程中经历了哪些氧化还原状态和丰度的变化？(3)硫氧还蛋白还原硫氧还蛋白所必需的酶的活性在萌发过程中是否发生变化？(4)硫氧还蛋白在其他类型的种子(如大豆)的萌发中是否起作用？这项研究将加深我们对硫氧还蛋白功能、酶调节和种子萌发的了解。%这一建议源于一项研究，在这项研究中，我们提出了一种酶系统(“硫氧还蛋白系统”)的证据，该系统作为已知的最早信号触发谷物(如小麦)的萌发。硫氧还蛋白系统的功能是：(1)激活谷物的储存蛋白，从而使它们能够被幼苗用作氮源和能量来源，以及(2)激活淀粉降解所需的酶，从而提高萌发早期的能量生产。这项研究的延伸表明硫氧还蛋白系统具有技术价值。将该系统应用于面粉中，强化面筋，提高面包品质。硫氧还蛋白系统还可以中和动物消化酶的植物蛋白抑制剂。将硫氧还蛋白系统应用于大豆等食品可能会提高它们的营养质量。涵盖这些用途的专利申请已经提交，硫氧还蛋白技术的商业化前开发已经开始。目前的项目代表了这项研究的基本方面的延伸。计划中的实验将显示硫氧还蛋白系统是否在小麦中具有额外的功能，以及该系统是否在其他类型种子的萌发中发挥重要作用。***